In a traditional public telephone network for connecting between telephones, voice signals are exchanged. Other audio data than the voice signals are now distributed over the traditional public telephone network, such as the Dial Q2 Service of Nippon Telephone Telegram, where a variety of commercial data audio signals are released from multiple providers via the switches of the network to the users. The service includes the network service carriers, instead of its providers, charging the fee of the commercial data and receiving it to the user who receives the commercial data. For transmitting the commercial data, the network service carrier has a data audio signal providing apparatus for delivering the audio data signal over the network to the user who selectively calls desired one of the Dial Q2 Service telephone numbers.
Recently, the commercial audio data can be received from the Internet where data is exchanged between computers. More specifically, thanks to the advanced CODEC technology and the perpetual development of the Internet as well as opening to every participant for the global communication over network-Internet-network systems and international network-dedicated network-network systems, a number of international telephone systems over the Internet are available these days.
However, such schemes for exchanging a variety of service data over the conventional communication network such as a public telephone network have been hardly provided. In a television broadcast system, an advertisement for requesting to visit a home page(HP) can be transferred only in one way to many unspecified users and cannot be involved to point-to-point communications.
In other words, the conventional advertisement distribution system delivers advertising items to many unspecified individuals and may thus force the user to receive the data.
FIG. 31 illustrates an Internet telephone system which has already been in service over the Internet. In the system, an ordinary telephone at the caller side is connected to an Internet telephone linked over the Internet to another Internet telephone gateway. And The telephone is further relayed from the another Internet telephone gateway to an ordinary telephone at the receiver side. That significantly contributes to reduce the charge of a long-distance call.
The procedure of calling on the system shown in FIG. 31 starts with connecting a call from the telephone 3112 at the caller side via a local telephone network 3113 to the caller side Internet telephone gateway 3114 to address the user identification number, the password number, and the receiver telephone number. Upon receiving the call from the telephone at the caller side, the caller side gateway 3114 selects one of Internet telephone gateways, as the receiver side gateway 3116, which exhibits the lowest charge for connecting the telephone 3118 at the receiver side. As a result, the connection to the receiver side telephone 3118 can be established over a receiver side local telephone network 3117.
However, the Internet telephone system shown in FIG. 32 requests the user at the caller side to call the Internet telephone gateway and address the user identification number, the password number, and the receiver side telephone number. Accordingly, the system requests a lot of steps for starting the Internet telephone call.
Also, in such a gateway-type Internet telephone system, the connection between the telephone of the caller or user and the Internet gateway is always turned on and charging to the caller even if the receiver side telephone is busy. In case that the receiver side telephone is busy throughout relatively a long period of time, the charge for the communication will be less expensive over the conventional public telephone network than the Internet telephone service.